Tirmidhi

1؎ :
The meaning is that whatever pains and hardships befall a believer in this world, Allah, by His grace, makes them an expiation for his sins.
But this is only in the case when the believer exercises patience.
And if, instead of patience, he displays impatience and begins to lament over fate, then not only will he be deprived of this reward,
but there is also the danger that he may have to bear the burden of further sins.

Hadith Commentary:
(1)
The reason for the occurrence of these hadiths is that the Messenger of Allah (sallallahu alayhi wa sallam) suddenly experienced pain at night, so due to the intensity of the pain, he began to turn from side to side on the bed.
Aisha (radi Allahu anha) said:
"O Messenger of Allah! If any one of us were to do this, you would become displeased."
At that time, he said:
"Righteous people are afflicted with trials and hardships."
(Musnad Ahmad: 159/6, 160)
In a narration of Ibn Hibban, it is mentioned that due to the pain, Allah, the Exalted, wipes away sins and also raises ranks.
(Sahih Ibn Hibban bi Tartib Ibn Balban: 167/7, No. 2906)

(2)
Its meaning is that pain becomes a cause for both the removal of punishment and the attainment of reward.
In any case, if a person experiences pain, it becomes an expiation for his sins, and if he endures it considering it as the decree of Allah, the Exalted, then it also becomes a means of attaining reward.
(Fath al-Bari: 131/10)

Hadith Gloss:
Vocabulary of the Hadith:
(1)
Wasab:
Illness.
(2)
Nasab:
Fatigue.
(3)
Saqam:
Sickness.
(4)
Huzn:
Distress.
(5)
Hamm:
Worry and anxiety that becomes a cause of suffering.